Related papers: Intergalactic shock fronts
Cold fronts were originally interpreted as being the result of subsonic/transonic motions of head-on merging substructures. This merger core remnant model is theoretically justified and hold relatively well for clusters that have clear…
X-ray observations were used to examine the complex temperature structure of Abell 85, a cool-core galaxy cluster. Temperature features can provide evidence of merging events which shock heat the intracluster gas. Temperature maps were made…
Recent high resolution observations by the {\it Chandra} X-ray satellite revealed various substructures in hot X-ray emitting plasmas in cluster of galaxies. For example, {\it Chandra} revealed the existence of sharp discontinuities in the…
Radio observations of a few cool-core galaxy clusters have revealed the presence of diffuse emission on cluster scales, similar to what was found in merging clusters in the form of radio halos. These sources might suggest that a minor…
We present an analysis of a highly asymmetric cluster merger from a Chandra observation of Abell 85. The merger shows significant disruption of the less massive subcluster from ram pressure effects. Nevertheless, a cold core, coincident…
Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. The basic properties of cluster mergers and their…
Shock waves driven in the intergalactic medium during the merging of galaxy clusters have been observed in X-ray imaging and spectroscopy. Fluid motions inferred from the shock strength and morphology can be compared to the cold dark matter…
Galaxy cluster mergers are representative of a wide range of physics, making them an excellent probe of the properties of dark matter and the ionized plasma of the intracluster medium. To date, most studies have focused on mergers occurring…
The outskirts of galaxy clusters are continuously disturbed by mergers and gas infall along filaments, which in turn induce turbulent flow motions and shock waves. We examine the properties of shocks that form within $r_{200}$ in sample…
Forward shocks by radio jets, driven into the intracluster medium, are one of the indicators that can be used to evaluate the power of the jet. Meanwhile high-angular-resolution X-ray observations show the Mach numbers of powerful radio…
We discuss two themes from Chandra and XMM-Newton observations of galaxies, groups, and clusters. First, we review observational aspects of cluster formation and evolution as matter accretes along filaments in A85 and A1367. We describe…
Cold fronts (CFs) are found in most galaxy clusters, as well as in some galaxies and groups of galaxies. We propose that some CFs are relics of merging between two shocks propagating in the same direction. Such shock mergers typically…
Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Major cluster mergers are the most energetic events in the Universe since the Big Bang. Some of the basic physical properties of mergers will be…
We report the discovery of spatially-extended, non-thermal-like emission components in Chandra X-ray spectra for five of a sample of seven massive, merging galaxy clusters with powerful radio halos. The emission components can be fitted by…
While dark matter self-interactions may solve several problems with structure formation, so far only the effects of two-body scatterings of dark matter particles have been considered. We show that, if a subdominant component of dark matter…
Deep Chandra exposures of the hot galaxy cluster 1E0657-56 have revealed that the cluster is observed shortly after the first core-passage of a massive infalling subcluster, which is preceded by a prominent bow shock with Mach number M~3.…
Evolutions of X-ray clusters of galaxies are studied by N-body (shell model) + mesh code (TVD) simulations on the assumption of spherical symmetry. We consider a density perturbation of $10^{15} M_{\odot}$ composed of dark matter and gas in…
Several types/classes of shocks naturally arise during formation and evolution of galaxy clusters. One such class is represented by accretion shocks, associated with deceleration of infalling baryons. Such shocks, characterized by a very…
Mergers of galaxy clusters are the most energetic events in the universe, driving shock and cold fronts, generating turbulence, and accelerating particles that create radio halos and relics. The galaxy cluster CL 0217+70 is a remarkable…
Mergers between galaxy clusters are an important stage in the formation of the large-scale structure of the Universe. Some of the mergers show a spectacular bow shock that formed as a result of recent passage of a smaller cluster through a…